Thanks for the feedback!
I didn't find this series when I was researching the topic initially.

I'll put my effort towards those problems instead.

Added a check in the preloaded code to disable requiring of the vm module

Sure!
I'll start with the map and filter functions.

Both map and filter's callback functions can take up to three parameters in the following order:

1. The current element
2. The current element's index
3. The array being iterated over

This means you can pass a callback that looks like this:

const arr = ["a", "b", "c"];
const res = arr.map((elem, index) => index);
console.log(res) // [0, 1, 2]

Reduce's callback follows a similar pattern:

1. An accumulator
2. The current element
3. The current element's index
4. The array being iterated over

Here's links to docs in MDN that explain it in further detail

1. map parameters
2. filter parameters
3. reduce parameters

Submitted a Javascript translation for this kata.

I have never seen someone write a for loop that way. That is an interesting way to do so.

This code makes me happy.